Z100′s annual Jingle Ball at Madison Square Garden Friday night (December 7) was bookended by an opening performance from One Direction and a closing headline set from Justin Bieber, with plenty of teen pop, British imports and R&B thrown in to make this year’s event an exceptionally youthful, zeitgeist-courting occasion — and a brisk one at that. Ten acts were squeezed into a set that came in just under four hours, with only Ne-Yo, Taylor Swift and Bieber getting enough set time to play anything close to a non-single.

Photos: Jingle Ball New York & Los Angeles

Alums from the UK “X Factor” were in particular abundance this year. Fresh off their first headlining gig at the Garden just this Monday, One Direction powered through their four biggest hits – “Live While We’re Young, ” “One Thing, ” “Little Things” and “What Makes You Beautiful” to rev up the crowd, transitioning seamlessly into a quick two-song set from Olly Murs. The stage was later graced by Cher Lloyd, who cameo’d to perform her top 20 hit “Want U Back, ” and Scooter Braun-backed boy band The Wanted, who played a lively, five-song set that included rising single “I Found You” and top 3 smash “Glad You Came. ” Singer Max George, the subject of an alleged club confrontation involving Lindsay Lohan in New York last week, wore a cheeky T-shirt brandishing the phrase “You Mad, Bro? ”

Singer-songwriter pop was also well represented, particularly in the form of Taylor Swift. Clad in a sparkly silver top and high-waisted red hot pants, Swift was backed by a giant “Red” setpiece – lest anyone forget the title of the album that’s already sold 2 . 2 million copies since its late October album. She powered through hits like “Love Story” and “You Belong To Me” and also gave one of her first live performances of new popstep single “I Knew You Were Trouble, ” believed to be inspired by her recently on-again romance with One Direction’s Harry Styles. “Have you ever seen someone for the very first time, locked eyes with them from across the room, and think to yourself, ‘Aw, he’s trouble, ‘” she told the crowd.

Jason Mraz also made a brief appearance on a separate mini-stage to serenade the crowd with top 10 ballad “I Won’t Give Up, ” the ubiquitous “I’m Yours” and his bubbly take on Christmas classic “Winter Wonderland. ” The intimate appearance was a warm-up to Mraz’s tour-closing show at the Garden this coming Monday.

Perhaps the night’s most ubiquitous presence was U. K. folk-pop singer Ed Sheeran, who wrote One Direction’s “Little Things, ” performed “Everything Has Changed” with Swift during her set and also played two of his own hits to a rapturous crowd, including hit “The A Team. ” Also playing his second show at the Garden this week following his opening slot for One Direction on Monday, Sheeran took in the moment by asking the crowd to light up their phones so he could take a picture.

On the R&B/hip-hop front, B. o. B. bounced through his 2010 hits “Magic, ” “Nothin’ On You” and “Airplanes” as well as this year’s top 20 charting “Both Of Us, ” for which he was joined by Swift on the hook. Ne-Yo scored the night’s penultimate slot and used the opportunity to rev up the crowd with summer anthem “Let’s Go, ” preview new singles “Don’t Make ‘Em Like You” and “Forever Now” and revisit his breakthrough hit “So Sick” before closing with a rousing rendition of current top 10 “Let Me Love You (Until You Learn To Love Yourself. )”